Make editor button work on Android 2.x

Apparently, the event object passed to hashchange callbacks in Android
Browser 2.x does not contain some properties available in newer browsers.
This patch changes the way the hash is fetched making the Router more
reliable on older browsers.

Change-Id: I25716393e7c8526c709f39375b06453a6dec26ef
Merge "Make editor button work on Android 2.x"